<?php

/**
 * @file
 * Functions to handle the s3 backup destination.
 */

/**
 * A destination for sending database backups to an s3 server.
 *
 * @ingroup backup_migrate_destinations
 */
class backup_migrate_destination_s3 extends backup_migrate_destination_remote {
  public $supported_ops = array('scheduled backup', 'manual backup', 'remote backup', 'restore', 'list files', 'configure', 'delete');
  public $s3 = NULL;
  public $cache_files = TRUE;
  public $got_library = FALSE;

  /**
   * Save to to the s3 destination.
   */
  public function _save_file($file, $settings) {
    if ($s3 = $this->s3_object()) {
      $path = $file->filename();
      if ($s3->putObject($s3->inputFile($file->filepath(), FALSE), $this->get_bucket(), $this->remote_path($file->filename()), S3::ACL_PRIVATE)) {
        return $file;
      }
    }
    return FALSE;
  }

  /**
   * Load from the s3 destination.
   */
  public function load_file($file_id) {
    require_once dirname(__FILE__) . '/files.inc';

    $file = new backup_file(array('filename' => $file_id));
    if ($s3 = $this->s3_object()) {
      $data = $s3->getObject($this->get_bucket(), $this->remote_path($file_id), $file->filepath());
      if (!$data->error) {
        return $file;
      }
    }

    return NULL;
  }

  /**
   * Delete from the s3 destination.
   */
  public function _delete_file($file_id) {
    if ($s3 = $this->s3_object()) {
      $s3->deleteObject($this->get_bucket(), $this->remote_path($file_id));
    }
  }

  /**
   * List all files from the s3 destination.
   */
  public function _list_files() {
    require_once dirname(__FILE__) . '/files.inc';

    $files = array();
    if ($s3 = $this->s3_object()) {
      $s3_files = $s3->getBucket($this->get_bucket(), $this->get_subdir());
      foreach ((array) $s3_files as $id => $file) {
        $info = array(
          'filename' => $this->local_path($file['name']),
          'filesize' => $file['size'],
          'filetime' => $file['time'],
        );
        $files[$info['filename']] = new backup_file($info);
      }
    }

    return $files;
  }

  /**
   * Get the form for the settings for this filter.
   */
  public function edit_form() {
    // Check for the library.
    // @todo Moe this to a constructor.
    $this->s3_object();

    // Do not return the form if library is not found.
    if (!$this->got_library) {
      return array();
    }

    $form = parent::edit_form();
    $form['scheme']['#type'] = 'value';
    $form['scheme']['#value'] = 'https';
    $form['host']['#default_value'] = @$this->dest_url['host'] ? $this->dest_url['host'] : 's3.amazonaws.com';

    $form['path']['#title'] = 'S3 Bucket';
    $form['path']['#default_value'] = $this->get_bucket();
    $form['path']['#description'] = 'This bucket must already exist. It will not be created for you.';

    $form['user']['#title'] = 'Access Key ID';
    $form['pass']['#title'] = 'Secret Access Key';

    $form['subdir'] = array(
      '#type' => 'textfield',
      '#title' => t('Subdirectory'),
      '#default_value' => $this->get_subdir(),
      '#weight' => 25,
    );
    $form['settings']['#weight'] = 50;

    return $form;
  }

  /**
   * Submit the form for the settings for the s3 destination.
   */
  public function edit_form_submit($form, &$form_state) {
    // Append the subdir onto the path.
    if (!empty($form_state['values']['subdir'])) {
      $form_state['values']['path'] .= '/' . trim($form_state['values']['subdir'], '/');
    }
    parent::edit_form_submit($form, $form_state);
  }

  /**
   * Generate a filepath with the correct prefix.
   */
  public function remote_path($path) {
    if ($subdir = $this->get_subdir()) {
      $path = $subdir . '/' . $path;
    }
    return $path;
  }

  /**
   * Generate a filepath with the correct prefix.
   */
  public function local_path($path) {
    if ($subdir = $this->get_subdir()) {
      $path = str_replace($subdir . '/', '', $path);
    }
    return $path;
  }

  /**
   * Get the bucket which is the first part of the path.
   */
  public function get_bucket() {
    $parts = explode('/', @$this->dest_url['path']);
    return $parts[0];
  }

  /**
   * Get the bucket which is the first part of the path.
   */
  public function get_subdir() {
    // Support the older style of subdir saving.
    if ($subdir = $this->settings('subdir')) {
      return $subdir;
    }
    $parts = explode('/', @$this->dest_url['path']);
    array_shift($parts);
    return implode('/', array_filter($parts));
  }

  /**
   *
   */
  public function s3_object() {
    $library_paths = array();

    // Try to use the Libraries module if available to find the path.
    if (function_exists('libraries_get_path')) {
      // @todo Defne this using hook_libraries().
      $path = libraries_get_path('s3-php5-curl');
      if (!empty($path)) {
        $library_paths[] = $path;
      }
      // If the library isn't defined, fall back to the default.
      else {
        $library_paths[] = 'sites/all/libraries/s3-php5-curl';
      }
    }
    else {
      $library_paths[] = 'sites/all/libraries/s3-php5-curl';
    }
    $library_paths[] = drupal_get_path('module', 'backup_migrate') . '/includes/s3-php5-curl';
    $library_paths[] = drupal_get_path('module', 'backup_migrate') . '/includes';

    foreach ($library_paths as $path) {
      if (file_exists($path . '/S3.php')) {
        require_once $path . '/S3.php';
        if (!$this->s3 && !empty($this->dest_url['user'])) {
          // The hostname can be overridden.
          $host = 's3.amazonaws.com';
          if (isset($this->dest_url['host'])) {
            $host = $this->dest_url['host'];
          }
          $this->s3 = new S3($this->dest_url['user'], $this->dest_url['pass'], FALSE, $host);
        }
        $this->got_library = TRUE;
        return $this->s3;
      }
    }
    drupal_set_message(t('A library is required to use an S3 destination. Please see <code>README.txt</code> for further instructions. The library could not be found in one of these locations: %locations.', array('%locations' => implode(', ', $library_paths))), 'error', FALSE);
    return NULL;
  }

}
